[//]:content-type-MARKDOWN-DONOT-DELETE To enhance the trading experience, Gate will soon launch a new depth channel **spot.obu** for spot trading. This new channel features optimized push logic and expanded depth levels. The details are as follows: **1. Channel Details** * Name：spot.obu * Parameter format：ob.{symbol}.{level} * Examples： ob.BTC_USDT.400（400 level）、ob.BTC_USDT.50（50 level） * Levels and update frequency: 400 levels: updated every 100ms 50 levels: updated every 20ms **2.Subscription and Push Rules** **1. Full Depth Push (full=true)** When the channel pushes a full depth update, the received depth data should completely replace the local depth, and the depth ID must be updated to the **u** field from the message. The server may resend full depth updates. * Upon subscribing to the channel, the first push will always be a full depth update. **2. Incremental Depth Push (full=false)** Incremental depth messages do not include the "full" field. Instead, the message contains "U" (the starting depth ID) and "u" (the ending depth ID). * If U = local depth ID + 1, the depth update is continuous: * Replace the local depth ID with the "u" value from the message. * If the "a" and "b" fields in the update are not empty, update the corresponding ask/bid sizes by price (level[0] is price, level[1] is size). If level[1] = "0", remove the corresponding price level from the local depth. * If U ≠ local depth ID + 1, the depth data is not continuous. In this case, unsubscribe from the symbol and resubscribe to obtain an initial full depth snapshot. **3. Subscription Limits** For the same depth stream of the same currency pair, only one subscription per connection is allowed. Duplicate subscriptions will return an error, e.g.: ``` { "error": { "code": 2, "message": "Alert sub ob.BTC_USDT.50" } } ``` **3. Examples of Operations and Data Push** **1.Subscription** **1.1Subscription request example** ``` from websocket import create_connection import json ws = create_connection("wss://ws-testnet.gate.io/v4/ws/spot") subscribe_msg = {"time": 1748572393, "channel": "spot.obu", "event": "subscribe", "payload": ["ob.BTC_USDT.50"]} ws.send(json.dumps(subscribe_msg)) print(ws.recv()) ``` **1.2 Subscription success response example** ``` {"time":1748572394,"time_ms":1748572394271,"conn_id":"b61f70b2e6bcca91","trace_id":"d2e2d92c3a7eabc3d5be52514ef508d2","channel":"spot.obu","event":"subscribe","payload":["ob.BTC_USDT.50"],"result":{"status":"success"},"requestId":"d2e2d92c3a7eabc3d5be52514ef508d2"} ``` **1.3 depth push example** ``` {"channel":"spot.obu","result":{"t":1748572394325,"full":true,"s":"ob.BTC_USDT.50","u":28606981,"b":[["105958.9","0.00908"],["105953.2","0.02426"],["105942.6","0.02074"],["105937.7","0.0099"],["105932","0.01731"],["105927.1","0.01796"],["105921.4","0.02041"],["105893.2","0.01265"],["105872","0.01895"],["70000","0.00005"],["49000.1","0.0002"],["66","0.05"]],"a":[["106009.9","0.01555"],["106038.1","0.00648"],["106048.7","0.01751"],["106059.3","0.00198"],["106080.5","0.01861"],["106091.1","0.02018"],["106101.7","0.01548"],["106112.3","0.01776"],["106122.9","0.01546"],["106133.5","0.02117"]]},"time_ms":1748572394325,"event":"update"} ``` **1.4 Incremental push example** ``` {"channel":"spot.obu","result":{"t":1748572395237,"s":"ob.BTC_USDT.50","u":28606989,"U":28606988,"b":[["66","0"]],"a":[["106009.9","0"]]},"time_ms":1748572395237,"event":"update"} ``` **2. Unsubscribe** **2.1 Unsubscribe request example** ``` from websocket import create_connection import json ws = create_connection("wss://ws-testnet.gate.io/v4/ws/spot") unsubscribe_msg = {"time": 1747054611, "channel": "spot.obu", "event": "unsubscribe", "payload": ["ob.BTC_USDT.50"]} ws.send(json.dumps(unsubscribe_msg)) print(ws.recv()) ``` **2.2 Unsubscribe response example** ``` {"time": 1743673617,"time_ms": 1743673617242,"id": 1,"conn_id": "7b06ff199a98ab0e","trace_id": "8f86e4021a84440e502f73fde5b94918","channel": "spot.obu","event": "unsubscribe","payload": ["ob.BTC_USDT.50"],"result": {"status": "success"}} ``` **4. Testnet Notice** This feature has been launched on the spot testnet. Please connect for testing via the following URL: WebSocket spot testnet URL: wss://ws-testnet.gate.io/v4/ws/spot Please adjust your integration according to the new rules. If you have any questions, please contact our support team. Gate Team May 30th, 2025 **Gateway to Crypto** Trade over 3,500 cryptocurrencies safely, quickly, and easily on Gate **Take Action Now** Sign up and claim up to $10,000 in welcome rewards Invite friends and earn a 40% commission **Stay Connected** Visit Gate's official website Download the Gate App | Desktop Follow us on X (Twitter) to get more bonuses Join our Telegram community to discuss trending topics Engage with our global community for the latest insights **Transparency & Security** Check our 100% Proof of Reserves

Gate Spot Depth Channel Upgrade Announcement